Shipping container



Oct. 24, 1967 w. P. BOYSEN 3,348,756

SHIPPING CONTAINER Filed Feb. 7, 1966 2 Sheets-Sheet 1 INVENTOR. Mun/20 P 50 ra /v Y w w r ATTORNEYS Oct. 24, 1967 w. P. BOYSEN 3,34

SHIPPING CONTAINER Filed Feb. 7, 1962 2 Sheets-Sheet 2 MHMM INVENTOR. M44220 P 5 x55 ATIORVEYS 11) M-% 1 United States Patent 3,348,756 SHIPPING CONTAINER Willard P. Boysen, Winnetka, Ill., assignor to Menasha Corporation, Chicago, 11]., a corporation of Wisconsin Filed Feb. 7, 1966, Ser. No. 525,548

Claims. (Cl. 229-37) ABSTRACT OF THE DISCLOSURE Container structure composed wholly of an imperforate, non-slotted corrugated paperboard blank, the marginal edges only of the blank being provided with moisture barrier means. A self-draining feature is provided by making the top and bottom cover panels terminate short of the median sector of the container and a suitable rigidifying means may also be provided on the end panels.

This application is a continuation-in-part of my copending application Ser. No. 402,283 filed Oct. 7, 1964, now abandoned.

The present invention relates to a container structure formed of corrugated paperboard, and provided with a means for waterproofing its edges to prevent ingress of moisture or water into the interior cavity of the corrugated board. The invention finds particular applicability in shipping containers for the shipment of perishables such as fresh fruits or vegetables, fish or other food items, flowers or the like, which require icing or refrigeration or the application of cold water during processing, packing, storage and/ or shipment.

The new container structure is composed of corrugated paperboard which retains its structural strength despite prolonged contact with moisture and water, and when exposed to rain or high humidity conditions. This is accomplished by forming the container from a completely imperforate rectangular corrugated paperboard blank free of slots, with all of the edges of the blank being protected against moisture penetration by a moisture barrier confined to the immediate proximity of the edges. The moisture barrier is sufiiciently flexible so that the blank may be scored and folded without damaging its moistureproof integrity.

In a specific application of the present invention, the blank is folded to provide side walls, end walls, a top, and a bottom. Additional panels in the blank define truncated triangular flaps arranged to lie in confronting relation against the end walls, the folding being such that the opposed panels which define the top and bottom of the container terminate short of the cent-erline thereof, leaving drainage slots at the top and bottom for the removal of water from the interior. The aforementioned triangular flaps may also be proportioned to provide pockets which snugly receive locking means to rigidify the end structures of the container.

An object of the present invention is to provide a container structure composed of corrugated paperboard which has its edges sealed to provide an airtight cavity within the corrugated board.

Another object of the invention is to provide a container structure having sealed edges which nevertheless can be scored and folded on conventional container forming machinery.

Another object of the invention is to provide an im proved corrugated board structure which has waterproof integrity preventing water penetration, making it possible to use a less expensive, corrugating medium and non-waterproof glue in the container structure.

Another object of the invention is to provide an improved shipping container for fresh produce, means, poultry, fish, and the like which are to be frozen or packedin ice.

A still further object of the invention is to provide an improved container with a simple but highly eflective rigidifying means at its ends.

Other objects and features of the present invention will become apparent to those skilled in the art from the following detailed description of the attached sheets of drawings in which:

FIGURE 1 is a plan view of a blank which can be used to form the container of the present invention;

FIGURE 2 is a view in perspective of the container While in the process of being folded;

FIGURE 3 is a view in perspective of the completed container, showing the locking means in position;

FIGURE 4 is a cross-sectional view taken substantially along the line IV-IV of FIGURE 3;

FIGURE 5 is a fragmentary view in cross-section taken substantially along the line V-V of FIGURE 3 illustrating the locking means and the end flaps more specifically;

FIGURE 6 is a view in perspective of a modified form of the container of the present invention;

FIGURE 7 is a cross-sectional view taken substantially along the line VIIVII of FIGURE 6;

FIGURE 8 is a fragmentary enlarged view of an edge structure of a corrugated paperboard treated in accordance with the present invention;

FIGURE 9 is a fragmentary cross-sectional view of a still further modified form of waterproofed edge structure; and

FIGURE 10 is an enlarged fragmentary cross-sectional view of still another modified form of the invention.

As shown in the drawings:

In FIGURE 1, reference numeral 10 indicates generally a blank which may be used for the construction of the container of the present invention. The blank 10 is composed of corrugated paperboard of the usual type, consisting of a corrugating medium and two liner sheets adhesively secured to the medium.

In the form of the invention shown in FIGURE 1, sealing of the edges is efiected by means of sealing tapes 11 and 12 which extend about the marginal edges of the blank in its long dimension, and sealing tapes 13 and 14 which are wrapped around the shorter or transverse marginal edges of the blank 10. The tapes prevent edgewise penetration of moisture into the container structure, but still permit scoring and folding of the blank into the completed container on box making machinery.

The blank 10 is provided with various fold lines for the purpose of defining the panels in the finished structure. These fold lines include a pair of parallel fold lines 16 and 17 running along the long dimension of the blank 10 which shall be referred to as the logitudinal dimension for purposes of orientation.

Perpendicular to the fold lines 16 and 17 are a plurality of transversely extending fold lines 18, 19, 20 and 21. As illustrated in FIGURE 1, the various fold lines define panels and flaps of the completed container structure. The fold lines 16, 17, 18 and the left hand marginal edge of the blank 10 serve to define one side panel 22 of the completed structure. The longitudinal fold lines 16 and 17 together with the transverse fold lines 18 and 19 serve to define one end panel 23. The longitudinally extending fold lines 16 and 17 together with the transversely extending fold lines 19 and 20 serve to define a side panel 24 which, in the completed form of the container, extends parallel to the side wall 22. Finally, the two longitudinally extending fold lines 16 and 17 together with the transversely extending fold lines 20 and 21 define another end panel 26 opposite to the end wall 23.

The portion of the blank extending between the fold line 21 and the extreme right hand marginal edge of the blank provides a tab generally indicated at numeral 27 which is received behind the tape 13 to form a manufacturers joint for the container. Suitable securing means such as eyelets 28 can be used to fasten the two overlapping surfaces together. If desired, imperforate securing means such as tape, staples, rivets or the like can also be used, or the two abutting faces can be joined together by means of a suitable adhesive.

The fold lines 16 and 18 and the upper left hand corner of the blank 10 define a panel 29 which forms part of the top structure of the completed container, as illustrated in FIGURES 2 and 3. The transverse width of the panel 29 is less than /2 the transverse width of the finished container. A comparable panel 31 is defined by the longitudinal fold line 17, the fold line 18, and the lower left hand corner of the blank 10. The panel 31 becomes part of the bottom structure of the finished container. A panel 32 similar to the panel 29, and of the same dimensions, is formed by fold lines 16, 19 and 20. A panel 33 similar to panel 31 and of the same dimensions is formed upon folding of the fold lines 17, 19 and 20. As best seen in FIGURE 4, the container in its folded condition has top forming panels 29 and 32 in spaced relation, since the transverse width of each panel is less than /2 the transverse dimension of the container. Similarly, the bottom forming panels 31 and 33 lie in opposed spaced relation, thereby providing a drainage slot 34 medially of the top of the container, and a drainage slot 35 medially of the bottom thereof.

As seen in FIGURE 1, there are provided additional fold lines 36 and 37 extending angularly from the intersections of fold lines 16 and 18, and 17 and 19 respectively, the fold lines 36 and 37 being arranged to be nonintersecting withi the body of the blank. Similarly, angularly extending, non-intersecting fold lines 38 and 39 extend from the intersections of the logitudinal ,fold line 17 and the transverse fold line 18, and fold line 17 and fold line 19, respectively. Other pairs of fold lines 41 and 42 are provided above the panel 26, and similarly angularly disposed, non-intersecting fold lines 43 and 44 are provided below the panel 26 in the blank 10.

As best seen in FIGURE 2, when the blank 10 is folded to provide the various side walls and end walls, the blank is also folded at the angularly disposed fold lines to provide .truncated, triangular flaps such as the flap 46 illustrated in FIGURE 2 and formed by folding the blank along the lines 43 and 44. Thus, as illustrated in FIGURE 3, the complete assembly includes a pair of such confronting truncated triangular flaps 46 and 47 along each end Wall of the finished container. These flaps can be secured to the box by tape, adhesive, strapping, or the like, or

may be secured by a locking means, as shown in FIG- URES 3, 6 and'7.

As best seen in FIGURE 3, the opposed flaps 46 and 47 define pockets which are arranged to receive a stiffening or rigidifying means such as a flat strip 51 of wood, plastic, metal or the like. The locking means is positioned by inserting it in alignment with the gap existing between the angularly extending walls of theflap, and then rotating it a slight amount until it is received in locked engagement within the pocket provided by the open flap structure. Thus, the strip 51 provides a simple .but highly effective means of rigidifying the end structures and locking the flaps in position without the necessity of adhesive or staples, or the like.

The form of the invention illustrated in FIGURES 6 and 7 is very similar in most particulars to that shown in FIGURES 1 to 5, and, accordingly, the same reference numerals have been applied to corresponding elements of structure. The difierence in this embodiment arises from the securing means which is used to rigidify the end structure. In the form of the invention illustrated in FIG URES 6 and 7, there is proivded a strip 52 of relatviely rigid but flexible material such as hard rubber, plastic, metal, or the like. The strip 52 has opposed hook-like end flanges 53 and 54, best illustrated in FIGURE 7, which hold the folded over end fiaps 46 and 47, for example, against the end wall panel 26. In other particulars, the structure shown in FIGURES 6 and 7 is the same as that shown in FIGURES 1 to 5.

It should be noted that the blank 10 is completely imperforate since it has no slots or other apertures through which water seepage could occur.

The most convenient means for securing the edge sealing in the corrugated paperboard structure is by impregnating the edges with a sealing compound such as a hot dip wax, microcrystalline wax, water-proof adhesives, synthetic thermoplastic materials, particularly polyethylene, or thermosetting materials. Aqueous emulsions of such compositions can also be employed. These impregnants serve to close off all openings around the edges of the box blank and thereby eliminate the need for a waterproof adhesive in the manufacture of the corrugated blank or the use of a moisture resistant corrugating medium. The impregnation of the corrugated board structure should be confined to the edges, andthis can easily be accomplished by partly immersing the edge of the board into the sealing compound or by wiping the compound into the corrugated openings. The impregnant forms a complete water barrier around the edges of the board providing an airtight cavity within the corrugated board. While the depth of impregnation can be varied depending upon the ultimate use to which the board will be put, it is suggested that the impregnation with the waterproofing compound be limited to one-quarter inch to one inch or so in the case of ordinary size boxes. If desired, the faces of the blank 10 can be provided with additional waterproofing material by coating the same with wax, resin, or other moisture repellant materials.

In the form of the invention shown in FIGURE 8 of the drawings, there is indicated generally a corrugated paperboard 61 having all of its edges impregnated with a waterproofing impregnant 62 covered by a tape 63 to protect against moisture penetration. Such tape is not necessary, of course, if adequate resistance to moisture penetration is achieved by the impregnant alone.

In the form of the invention shown in FIGURE 9, there is indicated a corrugated paperboard 64 wherein the edge portion 66 is reduced in thickness and is protected against moisture penetration by the application of a sealing tape 67 over the edge.

The modification of the invention shown in FIGURE 10 combines the modifications of FIGURES 8 and 9 in that it shows a corrugated paperboard 68 having a reduced thickness marginal edge 72 impregnated with an impregnant 71 consisting of a waterproofing material and further protected by means of a sealing tape 69 about its outer edge.

While a number of specific embodiments of the invention have been described and shown in the drawings, it

should be evident that various modifications can be madeto the described structures without departing from the scope of the present invention.

I claim as my invention:

1. A container structure wholly formed from a com: letely imperforate rectangular corrugated paperboard blank free of slots, all of the edges of said blank being protected against moisture penetration by a moisture barrier impregnant confined to the immediate proximity of said edges, said moisture barrier being sutficiently flexible so that said blank may be scored and folded without damaging its moisture-proof integrity.

2. The container structure of claim 1 in which said moisture barrier comprises a deposit of a moisture barrier material impregnating said blank to a slight extent inwardly from the edges thereof and sealing said edges against nq sture Penetra 3. The container structure of claim 1 in which said moisture barrier is a hot melt adhesive.

4. The container structure of claim 1 in which said moisture barrier is a microcrystalliue Wax.

5. The container structure of claim 1 in which said moisture barrier is a plastic material.

6. A self-draining container formed from a completely imperforate corrugated paperboard blank free of slots in Which the marginal edges of said blank are sealed against moisture penetration, said blank being folded along fold lines to provide panels defining side walls and end Walls, together with end fia-p defining panels which fold to form pairs of opposed truncated triangular flaps against said end Walls, said blank having additional panels thereon forming pairs of top and bottom covers for said container, said last named panels terminating short of the median center of said container, thereby providing drainage slots for said container.

7. The self-draining container of claim 6 having substantially rigid detachable locking means extending between said pairs of triangular flaps to rigidity the end structures of said container,

References Cited UNITED STATES PATENTS 915,579 3/1909 Ferres 22937 1,592,824 7/ 1926 Fairchild. 1,631,521 6/1927 Crowell. 2,058,757 10/1936 Bangs. 2,133,021 10/1938 Ferguson. 2,333,116 11/1943 Newsom 229-43 JOSEPH R. LECLAIR, Primary Examiner.

D. M. BOCKENEK, Assistant Examiner. 

6. A SELF-DRAINING CONTAINER FORMED FROM A COMPLETELY IMPERFORATE CORRUGATED PAPERBOARD BLANK FREE OF SLOTS IN WHICH THE MARGINAL EDGES OF SAID BLANK ARE SEALED AGAINST MOISTURE PENETRATION, SAID BLANK BEING FOLDED ALONG FOLD LINES TO PROVIDE PANELS DEFINING SIDE WALLS AND END WALLS, TOGETHER WITH END FLAP DEFINING PANELS WHICH FOLD TO FORM PAIRS OF OPPOSED TRUNCATED TRIANGULAR FLAPS AGAINST SAID END WALLS, SAID BLANK HAVING ADDITIONAL PANELS THEREON FORMING PAIRS OF TOP AND BOTTOM COVERS FOR SAID CONTAINER, SAID LAST NAMED PANELS TERMINATING SHORT OF THE MEDIAN CENTER OF SAID CONTAINER, THEREBY PROVIDING DRAINAGE SLOTS FOR SAID CONTAINER. 